#!/usr/bin/env bash
#
# Test qemu-img bitmap handling
#
# Copyright (C) 2018-2020 Red Hat, Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#

seq="$(basename $0)"
echo "QA output created by $seq"

status=1 # failure is the default!

_cleanup()
{
    _cleanup_test_img
    nbd_server_stop
}
trap "_cleanup; exit \$status" 0 1 2 3 15

# get standard environment, filters and checks
. ./common.rc
. ./common.filter
. ./common.nbd

_supported_fmt qcow2
_supported_proto file
_supported_os Linux
_require_command QEMU_NBD
# compat=0.10 does not support bitmaps
_unsupported_imgopts 'compat=0.10'

# Filter irrelevant format-specific information from the qemu-img info
# output (we only want the bitmaps, basically)
_filter_irrelevant_img_info()
{
    grep -v -e 'compat' -e 'compression type' -e 'data file' -e 'extended l2' \
            -e 'lazy refcounts' -e 'refcount bits'
}

echo
echo "=== Initial image setup ==="
echo

# Create backing image with one bitmap
TEST_IMG="$TEST_IMG.base" _make_test_img 10M
$QEMU_IMG bitmap --add -f $IMGFMT "$TEST_IMG.base" b0
$QEMU_IO -c 'w 3M 1M' -f $IMGFMT "$TEST_IMG.base" | _filter_qemu_io

# Create initial image and populate two bitmaps: one active, one inactive.
ORIG_IMG=$TEST_IMG
TEST_IMG=$TEST_IMG.orig
_make_test_img -b "$ORIG_IMG.base" -F $IMGFMT 10M
$QEMU_IO -c 'w 0 1M' -f $IMGFMT "$TEST_IMG" | _filter_qemu_io
$QEMU_IMG bitmap --add -g 512k -f $IMGFMT "$TEST_IMG" b1
$QEMU_IMG bitmap --add --disable -f $IMGFMT "$TEST_IMG" b2
$QEMU_IO -c 'w 3M 1M' -f $IMGFMT "$TEST_IMG" | _filter_qemu_io
$QEMU_IMG bitmap --clear -f $IMGFMT "$TEST_IMG" b1
$QEMU_IO -c 'w 1M 1M' -f $IMGFMT "$TEST_IMG" | _filter_qemu_io
$QEMU_IMG bitmap --disable -f $IMGFMT "$TEST_IMG" b1
$QEMU_IMG bitmap --enable -f $IMGFMT "$TEST_IMG" b2
$QEMU_IO -c 'w 2M 1M' -f $IMGFMT "$TEST_IMG" | _filter_qemu_io

echo
echo "=== Bitmap preservation not possible to non-qcow2 ==="
echo

TEST_IMG=$ORIG_IMG
$QEMU_IMG convert --bitmaps -O raw "$TEST_IMG.orig" "$TEST_IMG" &&
    echo "unexpected success"

echo
echo "=== Convert with bitmap preservation ==="
echo

# Only bitmaps from the active layer are copied
$QEMU_IMG convert --bitmaps -O qcow2 "$TEST_IMG.orig" "$TEST_IMG"
_img_info --format-specific | _filter_irrelevant_img_info
# But we can also merge in bitmaps from other layers.  This test is a bit
# contrived to cover more code paths, in reality, you could merge directly
# into b0 without going through tmp
$QEMU_IMG bitmap --add --disable -f $IMGFMT "$TEST_IMG" b0
$QEMU_IMG bitmap --add --merge b0 -b "$TEST_IMG.base" -F $IMGFMT \
     -f $IMGFMT "$TEST_IMG" tmp
$QEMU_IMG bitmap --merge tmp -f $IMGFMT "$TEST_IMG" b0
$QEMU_IMG bitmap --remove --image-opts \
    driver=$IMGFMT,file.driver=file,file.filename="$TEST_IMG" tmp
_img_info --format-specific | _filter_irrelevant_img_info

echo
echo "=== Merge from top layer into backing image ==="
echo

$QEMU_IMG rebase -u -F qcow2 -b "$TEST_IMG.base" "$TEST_IMG"
$QEMU_IMG bitmap --add --merge b2 -b "$TEST_IMG" -F $IMGFMT \
     -f $IMGFMT "$TEST_IMG.base" b3
_img_info --format-specific --backing-chain | _filter_irrelevant_img_info

echo
echo "=== Check bitmap contents ==="
echo

# x-dirty-bitmap is a hack for reading bitmaps; it abuses block status to
# report "data":false for portions of the bitmap which are set
IMG="driver=nbd,server.type=unix,server.path=$nbd_unix_socket"
nbd_server_start_unix_socket -r -f qcow2 \
    -B b0 -B b1 -B b2 -B b3 "$TEST_IMG"
$QEMU_IMG map --output=json --image-opts \
    "$IMG,x-dirty-bitmap=qemu:dirty-bitmap:b0" | _filter_qemu_img_map
$QEMU_IMG map --output=json --image-opts \
    "$IMG,x-dirty-bitmap=qemu:dirty-bitmap:b1" | _filter_qemu_img_map
$QEMU_IMG map --output=json --image-opts \
    "$IMG,x-dirty-bitmap=qemu:dirty-bitmap:b2" | _filter_qemu_img_map
$QEMU_IMG map --output=json --image-opts \
    "$IMG,x-dirty-bitmap=qemu:dirty-bitmap:b3" | _filter_qemu_img_map

nbd_server_stop

# success, all done
echo '*** done'
rm -f $seq.full
status=0